Systems and methods for threading a hot coil on a mill

ABSTRACT

Systems and methods of threading a metal substrate on a rolling mill include receiving a coil of the metal substrate. The method also includes uncoiling the metal substrate from the coil while the coil and guiding the metal substrate to a work stand of the rolling mill with a threading system.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a division of U.S. patent application Ser.No. 15/717,698 entitled “SYSTEMS AND METHODS FOR THREADING A HOT COIL ONA MILL” and filed on Sep. 27, 2017, which claims the benefit of U.S.Provisional Patent Application No. 62/400,426 entitled “ROTATING MAGNETHEAT INDUCTION” and filed on Sep. 27, 2016, and U.S. Provisional PatentApplication No. 62/505,948 entitled “ROTATING MAGNET HEAT INDUCTION” andfiled on May 14, 2017, the disclosures of which are hereby incorporatedby reference in their entireties.

Additionally, the present application is related to U.S. Non-provisionalpatent application Ser. No. 15/716,559 to Antoine Jean Willy Pralong etal., entitled “SYSTEMS AND METHODS FOR NON-CONTACT TENSIONING OF A METALSTRIP” filed Sep. 27, 2017, U.S. Non-provisional patent application Ser.No. 15/716,608 to David Anthony Gaensbauer et al., entitled “COMPACTCONTINUOUS ANNEALING SOLUTION HEAT TREATMENT” filed Sep. 27, 2017, andU.S. Non-provisional patent application Ser. No. 15/716,887 to AntoineJean Willy Pralong et al., entitled “ROTATING MAGNET HEAT INDUCTION”filed Sep. 27, 2017, the disclosures of which are hereby incorporated byreference in their entireties.

FIELD OF THE INVENTION

This application relates to metal processing and, more particularly, tosystems and methods for threading a coil of a metal substrate on arolling mill.

BACKGROUND

During metal processing, sometimes a metal substrate is uncoiled from acoil of the metal substrate. However, the traditional method ofuncoiling the metal substrate from the coil may cause damage such asscratching or other defects to the metal substrate.

SUMMARY

The terms “invention,” “the invention,” “this invention” and “thepresent invention” used in this patent are intended to refer broadly toall of the subject matter of this patent and the patent claims below.Statements containing these terms should be understood not to limit thesubject matter described herein or to limit the meaning or scope of thepatent claims below. Embodiments of the invention covered by this patentare defined by the claims below, not this summary. This summary is ahigh-level overview of various embodiments of the invention andintroduces some of the concepts that are further described in theDetailed Description section below. This summary is not intended toidentify key or essential features of the claimed subject matter, nor isit intended to be used in isolation to determine the scope of theclaimed subject matter. The subject matter should be understood byreference to appropriate portions of the entire specification of thispatent, any or all drawings, and each claim.

According to some examples, a method of threading a metal substrate on arolling mill includes receiving a coil of the metal substrate. Themethod also includes uncoiling the metal substrate from the coil. Invarious examples, the method includes guiding the metal substrate to awork stand of the rolling mill with a threading system.

According to certain examples, a system for threading a metal substrateon a rolling mill includes a threading carriage with a gripperconfigured to grip a metal substrate. In certain cases, the system alsoincludes a track extending between an unwind mandrel and a work stand ofthe rolling mill. In some examples, the threading carriage is movablealong the track, and the threading carriage is configured to guide andapply tension to the metal substrate between the unwind mandrel and thework stand.

Various implementations described in the present disclosure can includeadditional systems, methods, features, and advantages, which cannotnecessarily be expressly disclosed herein but will be apparent to one ofordinary skill in the art upon examination of the following detaileddescription and accompanying drawings. It is intended that all suchsystems, methods, features, and advantages be included within thepresent disclosure and protected by the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and components of the following figures are illustrated toemphasize the general principles of the present disclosure.Corresponding features and components throughout the figures can bedesignated by matching reference characters for the sake of consistencyand clarity.

FIG. 1 is a schematic of a system for threading a coil on a millaccording to aspects of the present disclosure.

FIG. 2 is another schematic of the system FIG. 1.

FIG. 3 is another schematic of the system of FIG. 1.

FIG. 4 is another schematic of the system of FIG. 1.

FIG. 5 is a schematic of a system for threading a coil on a millaccording to aspects of the present disclosure.

FIG. 6 is a photograph of a system for threading a coil on a millaccording to aspects of the present disclosure.

FIG. 7 is another photograph of the system of FIG. 6.

FIG. 8 is a photograph of a gripper of the system of FIG. 6.

FIG. 9 is another photograph of the gripper of FIG. 8 gripping a metalsubstrate.

FIG. 10 is a photograph of a system for threading a coil on a millaccording to aspects of the present disclosure.

FIG. 11 is another photograph of the system of FIG. 10.

FIG. 12 is another photograph of the system of FIG. 10.

FIG. 13 is another photograph of the system of FIG. 10.

FIG. 14 is another photograph of the system of FIG. 10.

FIG. 15 is another photograph of the system of FIG. 10.

FIG. 16 is a schematic of a system for threading a coil on a millaccording to aspects of the present disclosure.

FIG. 17 is a schematic of a gripping roll for a system for threading acoil on a mill according to aspects of the present disclosure.

FIG. 18 is a schematic of a gripper gripping a metal substrate accordingto aspects of the present disclosure.

DETAILED DESCRIPTION

The subject matter of examples of the present invention is describedhere with specificity to meet statutory requirements, but thisdescription is not necessarily intended to limit the scope of theclaims. The claimed subject matter may be embodied in other ways, mayinclude different elements or steps, and may be used in conjunction withother existing or future technologies. This description should not beinterpreted as implying any particular order or arrangement among orbetween various steps or elements except when the order of individualsteps or arrangement of elements is explicitly described.

Disclosed are systems and methods for threading a coil of a metalsubstrate on a mill. Aspects and features of the present disclosure canbe used with coils of any suitable metal substrate, and may beespecially useful with coils of aluminum or aluminum alloys.Specifically, desirable results can be achieved when uncoiling alloyssuch as 2xxx series, 3xxx series, 4xxx series, 5xxx series, 6xxx series,7xxx series, or 8xxx series aluminum alloys. For an understanding of thenumber designation system most commonly used in naming and identifyingaluminum and its alloys, see “International Alloy Designations andChemical Composition Limits for Wrought Aluminum and Wrought AluminumAlloys” or “Registration Record of Aluminum Association AlloyDesignations and Chemical Compositions Limits for Aluminum Alloys in theForm of Castings and Ingot,” both published by The Aluminum Association.

In some cases, the systems and methods disclosed herein may be used withnon-ferrous materials, including aluminum, aluminum alloys, magnesium,magnesium-based materials, titanium, titanium-based materials, copper,copper-based materials, steel, steel-based materials, bronze,bronze-based materials, brass, brass-based materials, composites, sheetsused in composites, or any other suitable metal, non-metal orcombination of materials. The article may include monolithic materials,as well as non-monolithic materials such as roll-bonded materials, cladmaterials, composite materials (such as but not limited to carbonfiber-containing materials), or various other materials. In onenon-limiting example, the systems and methods can be used to heat metalarticles such as aluminum metal strips, slabs, blanks, or other articlesmade from aluminum alloys, including aluminum alloys containing iron.

Aspects and features of the present disclosure can be used with coils ofa metal substrate at any temperature, and may be especially useful withcoils at elevated temperatures of at least 450° C. In other examples,aspects and features of the present disclosure can be used with coils ofa metal substrate at a temperature less than 450° C., such as less than100° C. For example, in some cases, aspects and features of the presentdisclosure can be used with coils of a metal substrate at roomtemperature that are to be heated or hot metal substrate at atemperature below 450° C. that is to be cooled down. As used herein, themeaning of “room temperature” can include a temperature of from about15° C. to about 30° C., for example about 15° C., about 16° C., about17° C., about 18° C., about 19° C., about 20° C., about 21° C., about22° C., about 23° C., about 24° C., about 25° C., about 26° C., about27° C., about 28° C., about 29° C., or about 30° C.

An example of a threading system 100 for threading a metal substrate 102from a coil 106 on a rolling mill 104 is illustrated in FIGS. 1-4.

The rolling mill 104 includes at least one work stand 120. In someexamples, the rolling mill 104 includes a plurality of work stands 120,such as two work stands 120, three work stands 120, four work stands120, or any other desired number of work stands 120. The work stand 120includes a pair of vertically aligned work rolls 122. In some examples,the work stand 120 also includes backup rolls 124 that support the pairof work rolls 122. In various examples, the work stand 120 also includesintermediate rolls. A roll gap 126 is defined between the work rolls122.

During processing, the metal substrate 102 is passed through the rollgap 126 such that the work rolls 122 reduce the thickness of the metalsubstrate 102 to a desired thickness and impart particular properties onthe metal substrate 102. The particular properties imparted may dependon the composition of the metal substrate 102. In some examples, therolling mill 104 may be a hot rolling mill that is configured to rollthe metal substrate 102 when the temperature of the metal substrate 102is above the recrystallization temperature of the metal substrate 102.In other examples, the rolling mill 104 may be a cold rolling mill thatis configured to roll the metal substrate 102 when the temperature ofthe metal substrate 102 is below the recrystallization temperature ofthe metal substrate 102. In various other examples, the rolling mill 104may be a warm rolling mill that is configured to roll the metalsubstrate 102 when the temperature of the metal substrate 102 is belowthe recrystallization temperature but above the temperature during coldrolling.

In various examples, the coil 106 is supported on an unwind mandrel 108.In some cases, the unwind mandrel 108 is a predetermined distance fromthe work stand 120. In certain non-limiting examples, the predetermineddistance from the work stand 120 to the unwind mandrel 108 is less thanabout 20 meters, such as less than about 15 meters, such as less thanabout 10 meters. In some examples, the predetermined distance is fromabout 3 meters to about 5 meters. In other examples, the predetermineddistance is greater than about 20 meters. The predetermined distance maybe changed depending on the metal substrate to be processed, a desiredmill setup, or various other considerations.

In some examples, the unwind mandrel 108 is configured to receive and/orsupport the coil 106 while the coil 106 is at an elevated temperature.In some examples, the elevated temperature is greater than 450° C.,although it need not be. In some cases, the elevated temperature is fromabout 450° C. to about 560° C. In other examples, the elevatedtemperature is greater than 560° C. In certain cases, the elevatedtemperature is less than a melting point of the metal substrate. In oneexample where the metal substrate 102 is aluminum or an aluminum alloy,the elevated temperature is less than a melting point of the aluminum oraluminum alloy. In various examples, it may be beneficial to useelevated coil temperatures to achieve an elevated roll entry temperatureat a work stand of a rolling mill (such as a temperature greater than500° C., among others). Elevated coil temperatures may also be used sothat the coils can be rolled directly from a homogenization furnace. Inother examples, the coil 106 may be less than 450° C. In certainexamples, the coil 106 may be at room temperature or various othertemperatures less than 450° C.

The unwind mandrel 108 defines an axis of rotation 110 about which thecoil 106 is rotated to unwind the metal substrate 102. In the threadingsystem 100 illustrated in FIGS. 1-4, the coil 106 is mounted on theunwind mandrel 108 such that the coil 106 is rotated in the directionindicated by arrow 112 to uncoil the metal substrate 102. Uncoiling inthe direction indicated by arrow 112 is generally known as“under-winding.” In the under-winding configuration, an unroll point114, or the point where the metal substrate 102 separates from the coil106, is per definition below the axis of rotation 110. In variousexamples, uncoiling the metal substrate 102 by under-winding allows forthe weight of the outermost layer of the coil 106 to hold the remainderof the coil 106 tightly on the unwind mandrel 108. Under-winding mayalso allow for the outermost layer of the coil 106 (also known as theouter lap of the coil) to separate from the rest of the coil 106 usinggravity. In other examples, the coil 106 is mounted on the unwindmandrel 108 such that the coil 106 is rotated in the opposite direction,which is known as “over-winding” and discussed in detail below withrespect to FIG. 5.

In both the under-winding and over-winding configurations, a passline116 is defined between the unroll point 114 and the roll gap 126 of thework stand 120. In some examples, the passline 116 extends at a non-zeroangle relative to a horizontal plane. In other examples, the passline116 is substantially parallel to the horizontal plane. FIGS. 1-4illustrate examples where the passline 116 is substantially parallel tothe horizontal plane. In various examples, the unwind mandrel 108 isvertically adjustable such that as the coil 106 unwinds (and thediameter of the coil 106 decreases), the relative angle of the passline116 to the horizontal plane can be maintained.

As illustrated in FIGS. 1-4, in various examples, the threading system100 includes a threading carriage 128 that is configured to guide themetal substrate 102 from the coil 106 to the work stand 120 to threadthe metal substrate 102 in the roll gap 126. In some cases, thethreading carriage 128 is movable along a track 134 that supports thethreading carriage 128. In various examples, the threading carriage 128optionally includes wheels, rollers, sliders, or various other suitablemovement mechanisms that allow for movement of the threading carriage128 along the track 134. As illustrated in FIGS. 1-4, the track 134extends at least partially between the unwind mandrel 108 and the workstand 120. In some examples, various mechanical movers may move thethreading carriage 128 along the track 134. Mechanical movers include,but are not limited to, chains, wires (see, e.g., wires 702 in FIG. 7),rack and pinion, drive motors, robotic arms, or various other suitabledevices for moving the threading carriage 128 along the track 134. Invarious cases, the threading carriage 128 is moved along the track 134towards the work stand 120 at a linear speed that matches orapproximates a rotational speed of the coil 106.

The threading carriage 128 includes a gripper 130, which is configuredto selectively grip and release the metal substrate 102 as described indetail below. The gripper 130 may be a gripping wedge (see FIGS. 6-9), apair of gripping rolls (see FIGS. 10-15), a clamp, or various othersuitable mechanisms for selectively gripping and releasing the metalsubstrate 102. In various examples, the gripper 130 is configured togrip the metal substrate 102 proximate to a leading edge 132 of themetal substrate 102 as it unwound from the coil 106. In some examples asillustrated in FIGS. 1-4, the gripper 130 is configured to grip themetal substrate 102 at a position along the metal substrate 102 that isoffset from the leading edge 132 of the metal substrate 102. By grippingthe metal substrate 102 at the offset position from the leading edge132, the threading carriage 128 can thread the leading edge 132 of themetal substrate into the roll gap 126 without contacting the work rolls122 (or other portions of the work stand 120) (see FIG. 3). In certainexamples, the gripper 130 may grip the metal substrate 102 at a positionthat is about 500 mm from the leading edge 132. In various examples, theoffset position may be adjusted as desired to be greater than or lessthan 500 mm. In other examples, the gripper 130 may grip the metalsubstrate 102 at or near the leading edge 132 such that the leading edge132 may be into the roll gap 126 without the carriage 128 contacting thework rolls 122.

Once the threading carriage 128 guides the metal substrate 102 and theleading edge 132 is threaded into the roll gap 126, the gripper 130 mayrelease the metal substrate 102. In some examples, a release on thegripper 130 causes the gripper 130 to release the metal substrate 102.The release may be various suitable release mechanisms that may beautomatic (e.g., spring loaded hooks, pins, clips, clasps, or othersuitable automatic release mechanisms) or manual (e.g., mechanisms thatrequire an operator). As one example, the release may be an automaticrelease that is triggered by a triggering device when the leading edge132 is threaded into the roll gap 126. In some cases, such as where thegripper 130 includes gripping rolls, the gripping rolls could continueto grip the metal substrate 102 after the leading edge 132 is threadedinto the roll gap 126 and the gripping rolls are at their maximumposition downstream (e.g., the gripping rolls are at a positionproximate to the work stand 120. In such cases, the gripping rolls mayrotate and further help thread the metal substrate 102. In certainexamples, the gripping rolls may continue to thread the metal substrate102 during open bite threading where the work rolls 122 are open and donot “bite” the metal substrate 102 during threading. In other examples,the threading carriage 128 continues to grip the metal substrate 102after the metal substrate 102 is threaded into the roll gap. In certainexamples, the threading carriage 128 may disengage from the metalsubstrate 102 when the leading edge of the metal substrate is gripped bya recoiler 111 (see FIG. 16).

In certain optional examples, when the metal substrate 102 is completelyunrolled from the unwind mandrel 108, the gripper 130 may grip the metalsubstrate 102 at a position along the metal substrate 102 that is offsetfrom or at the trailing edge 133 of the metal substrate 102 (see FIG.4). By gripping the metal substrate 102 at or proximate to the trailingedge 133, the threading carriage 128 may guide the trailing edge 133 tothe work stand 120. Once the threading carriage guides the metalsubstrate 102 such that the trailing edge 133 is proximate to the rollgap 126, the gripper 130 may release the metal substrate 102.

As illustrated in FIGS. 1-4, in some examples, the threading system 100includes at least one rotating magnet 136 that is configured tosupport/stabilize the metal substrate 102 as it is guided to the workstand 120 without contacting the metal substrate 102. In variousexamples, a plurality of rotating magnets 136 are provided. In someexamples, the rotating magnets 136 are positioned below or above thepassline 116. In other examples, some rotating magnets 136 arepositioned below the passline 116 and other rotating magnets 136 arepositioned above the passline 116. In certain examples, a rotatingmagnet set includes a pair of vertically aligned rotating magnets 136 onopposite sides of the passline 116. In some cases, each rotating magnet136 of the rotating magnet set can be positioned equidistance from thepassline 116 to avoid pulling the metal substrate 102 away from thepassline 116. In some examples, the rotating magnets 136 of the rotatingmagnet set rotate in opposite directions, although they need not inother examples. In various other examples, rotating magnets 136 abovethe passline 116 may be offset from rotating magnets 136 below thepassline 116.

Each rotating magnet 136 can include one or more permanent magnets orelectromagnets. As the metal substrate 102 passes along the passline 116above or below a rotating magnet 136 or between a pair of rotatingmagnets 136, the rotating magnets 136 apply a vertical repulsive forceto the metal substrate 102. The vertical repulsive force from therotating magnets 136 provides vertical stabilization and allows themetal substrate 102 to pass over and/or between the rotating magnets 136without contacting the rotating magnets 136 (e.g., to float along thepassline 116). In some examples with a plurality of rotating magnets136, a downstream rotating magnet (i.e., a rotating magnet 136 closer tothe work stand 120) can offset tension induced by an upstream rotatingmagnet 136 (i.e., a rotating magnet 136 closer to the coil 106). Invarious examples, tension can be offset by the downstream rotatingmagnet 136 by rotating it in a direction that is opposite the directionof rotation of the upstream rotating magnet 136. As one example, anupstream rotating magnet 136 may rotate in a downstream direction (e.g.,in a clockwise direction in FIG. 1) while a downstream rotating magnet136 may rotate in an upstream direction (e.g., in a counter-clockwisedirection in FIG. 1).

In some examples, the plurality of rotating magnets 136 are alsopositioned and configured to heat the metal substrate 102 so it has adesired roll entry temperature as it enters the work stand 120. In somecases, the metal substrate has a roll entry temperature betweenapproximately 20° C. and approximately 600° C., although various othertemperatures may be used depending on particular application.

In some examples, a lap slippage monitor or other suitable monitor maybe provided to optically monitor (or monitor through other suitabletechniques) the metal substrate 102 between the coil 106 and therotating magnet 136 to ensure that no tension or no slippage in the coilis generated in the metal substrate 102.

In some optional examples, the threading system 100 includes at leastone quench 138. In other examples, the quench 138 may be omitted (see,e.g., FIG. 10). The number and location of the quenches 138 may bevaried as desired. For example, in some cases, as illustrated in FIGS.1-4, the threading system 100 includes two quenches 138, with one quench138 above the passline 116 and one quench 138 below the passline 116. Inthe example illustrated in FIGS. 1-4, the quenches 138 are positionedbetween rotating magnets 136. In other examples, the quenches 138 may beat various other locations and may have fewer or additional quenches138. The quenches 138 are configured to spray or otherwise reduce thetemperature of the metal substrate 102 as it is fed to the work stand120. The quenches 138 may reduce the temperature of the metal substrate102 down to various temperatures depending on whether the mill 104 is ahot mill, cold mill, or warm mill. In some examples, the quenches 138also reduce or offset any nominal heating in the metal substrate 102that may be caused by the rotating magnets 136. In some cases, thequenches 138 add stiffness to the metal substrate 102.

In some cases, using quenches 138 and/or rotating magnets 136 to floatand optionally heat the metal substrate 102 optimizes the thermaltreatment of the metal substrate 102 during threading to help increaserecovery, meaning that less of the metal substrate 102 is lost to scrapor discarded due to unwanted and/or undesired metallurgical propertiesin the metal substrate and/or various other defects in the metalsubstrate that might otherwise occur. During processing, the head ortail of the metal substrate 102 may not be at the target temperature.Through heating and quenching, the head and/or tail of the metalsubstrate 102 may be better controlled to be at the target temperature(e.g., and have the desired metallurgical properties), which increasesthe recovery of the metal substrate 102 (i.e., less of the metalsubstrate 102 is lost to scrap or discarded due unwanted and/orundesired metallurgical properties as well various other defects in themetal substrate).

In various examples, after a first quench 138, the rotating magnets 136may be used to increase the back tension towards the mill 104 at eachrotating magnet 136. This may improve the rolling conditions in the rollgap 126 as well as the quench conditions because the metal substrate 102may be held more stable on the passline 116 in the quench zones.

FIG. 5 illustrates an example of the threading system 100 where the coil106 is mounted on the unwind mandrel 108 such that the coil 106 isrotated in the direction indicated by arrow 502 to unwind the metalsubstrate 102. Unwinding in the direction indicated by arrow 502 isgenerally known as “over-winding,” and in such configurations, theunroll point 114 is generally above the axis of rotation 110.

In some optional examples, a foil layer 504 is wound with the metalsubstrate 102 within the coil 106 to separate adjacent layers of themetal substrate 102. The foil layer 504 may be included to preventinterlap scratches in the coil 106, which may occur during decoiling. Invarious examples, the foil layer 504 may be included with coils 106 atelevated temperatures, although they may also be included with coils 106at various other temperatures. In certain examples, the foil layer 504includes a metal having a higher melting point than a melting point ofthe metal substrate 102. In some cases, the foil layer 504 may have ahardness that is less than a hardness of the metal substrate 102. In theexample illustrated in FIG. 5, the metal substrate 102 includes aluminumor an aluminum alloy, and the foil layer 504 includes steel.

While the foil layer 504 may be included with the metal substrate 102within the coil 106, the foil layer 504 is removed during threading anduncoiling of the metal substrate 102. In various examples, uncoiling themetal substrate 102 in the over-winding direction may facilitateseparating a foil layer from the coil 106 as illustrated in FIG. 5,although in other examples, the foil layer may be separated from thecoil 106 in the under-winding configuration.

FIGS. 6-9 illustrate an example of a threading system 600 that issimilar to the threading system 100. In the threading system 600, thegripper 130 of the threading carriage 128 includes a gripping wedge 602.The gripping wedge 602 includes a base 606 and a top 608. The top 608 ispositionable relative to the base 606 between a gripping position (seeFIG. 6) to grip the metal substrate 102 and a release position (seeFIGS. 8 and 9) to release the metal substrate 102. Optionally, in somecases, the gripping wedge 602 includes guides 610A-B, which mayfacilitate the initial positioning of the metal substrate 102 relativeto the threading carriage 128.

In some examples, the gripping wedge 602 includes at least one ridge 604that is configured to crimp the metal substrate 102 while the grippingwedge 602 grips the metal substrate 102 and impart at least one lateralcurvature across a width of the metal substrate 102. The ridge 604 maybe on the base 606 or the top 608 of the gripping wedge 602. In variousexamples, any number of ridges 604 may be provided on the base 606and/or the top 608. In some examples, the number of ridges 604 may bevaried depending on a desired lateral curvature pattern. For example,ridges 604 may be provided to impart a single curve, a plurality ofcurves (e.g., pattern similar to a sine wave), or any other pattern asdesired. In some examples, a height of the ridges 604, which is adistance that the ridge 604 projects from the base 606 and/or top 608,may be adjusted to adjust a radius of curvature of the lateralcurvature. In certain examples, the height of one ridge 604 may bedifferent from a height of another ridge 604. In some examples, thelateral curvature imparted by the gripping wedge 602 may allow for theleading edge 132 of the metal substrate 102 to remain closer to thepassline 116 (i.e., not to sag as illustrated in FIG. 9), which mayfacilitate threading of the leading edge 132 into the roll gap 126.

FIG. 18 illustrates a non-limiting example of a gripping wedge 1802 thatis similar to the gripping wedge 602 and includes three ridges 604—tworidges 604 on the base 606 and one ridge 608 on the top 608. Asillustrated, the gripping wedge 1802 grips the metal substrate 108 andimparts three lateral curvatures 1804 across a width of the metalsubstrate 102.

FIGS. 10-15 illustrate an example of a threading system 1000 that issimilar to the threading system 100. In the threading system 1000, thegripper 130 of the threading carriage 128 includes gripping rolls 1002.In some examples, the gripping rolls 1002 are vertically aligned and arevertically movable between a release position (see FIG. 10) and agripping position (see FIG. 13). The threading system 1000 also includesan optional pinch roll 1202. The pinch roll 1202 is configured to directthe metal substrate 102 from the unwind mandrel 108 to the threadingcarriage 128. In various examples, the pinch roll 1202 is configured torotate at a rotational speed that matches a linear speed of movement ofthe metal substrate 102.

In certain examples, the gripping rolls 1002 are configured to addstiffness to the metal substrate 102 similar to the gripping wedge 602by crimping the metal substrate 102 with the gripping rolls 1002 suchthat the metal substrate includes at least one lateral curvature acrossthe width of the metal substrate. In certain examples, the grippingrolls 1002 may crimp the metal substrate 102 through bending of thegripping rolls 1002. In some examples, the gripping rolls 1002 have aprofile suitable for crimping the metal substrate. As one non-limitingexample, the gripping rolls 1002 may have a variable radius along theaxis of the rolls 1002. For example, FIG. 17 illustrates an example of agripping roll 1002 where the gripping roll 1002 includes at least twodifferent diameters 1702 and 1704. Gripping rolls 1002 having variousother diameter profiles or shapes may be used as desired. In otherexamples, one or more vertically adjustable gripping rolls 1002 may beprovided across the strip width, and each gripping roll 1002 may bevertically adjusted to provide the desired crimp in the metal substrate.In other examples, multiple narrow gripping rolls 1002 may be providedon the top and/or bottom of the metal substrate, and the gripping rolls1002 may be vertically shifted to give the lateral curvature in thestrip. Various other suitable mechanisms for crimping the metalsubstrate 1002 with or without the gripping rolls 1002 may be utilized.

A method of threading the metal substrate 102 on the rolling mill 104 isalso disclosed. Referring to FIG. 1, in some examples, the methodincludes receiving the coil 106 of the metal substrate 102. The coil 106may be at an elevated temperature, which may be greater than 450° C.,although it need not be. For example, in other cases, the coil 106 maybe at room temperature, or various other temperatures less than 450° C.In certain examples, a temperature of the coil 106 may at leastpartially depend on the material of the metal substrate 102.

The method includes uncoiling the metal substrate 102 from the coil 106.In some examples, the coil 106 includes a weld that secures the leadingedge 132 of the metal substrate 102 against the coil 106. In such cases,uncoiling the metal substrate 102 includes breaking the weld with apeeler knife or other suitable device. In some examples, uncoiling themetal substrate 102 includes uncoiling the metal substrate 102 while thecoil 106 is at the elevated temperature. In other examples, uncoilingthe metal substrate 102 includes uncoiling the metal substrate 102 whilethe coil 106 is at any temperature. In various examples, the coil 106 ismounted on the unwind mandrel 108 such that uncoiling the metalsubstrate 102 includes under-winding the metal substrate 102 from thecoil 106 (see FIGS. 1-4). In other examples, the coil 106 is mounted onthe unwind mandrel 108 such that uncoiling the metal substrate 102includes over-winding the metal substrate 102 from the coil 106 (seeFIG. 5). In certain examples, if the coil 106 includes the foil layer504 between adjacent layers of the metal substrate 102, uncoiling themetal substrate 102 from the coil 106 includes separating the foil layer504 from the metal substrate 102 (see FIG. 5). In some examples,uncoiling the metal substrate 102 also includes maintaining apredetermined feed angle of a passline 116 relative to the roll gap 126by adjusting a vertical position of the unwind mandrel 108, whichvertically adjusts the position of the coil 106.

The method also includes guiding the metal substrate 102 to the workstand 120 of the rolling mill 104. In some examples, guiding the metalsubstrate 102 to the work stand 120 includes guiding the metal substrate102 to a threading carriage (such as the threading carriage 128) andgripping the metal substrate 102 with a gripper (such as gripper 130) ofthe threading carriage 128 (see FIG. 1). After the threading carriage128 grips the metal substrate 102, the method includes moving thethreading carriage 128 towards the work stand 120 (see FIGS. 1-4). Invarious examples, the threading carriage 128 grips the metal substrate102 at a position that is offset from the leading edge 132 of the metalsubstrate such that when the leading edge 132 is fed into the roll gap126 of the work stand 120, the threading carriage 128 is spaced apartfrom work rolls 122 of the work stand 120 (see FIG. 3)

In certain optional examples, the metal substrate 102 is guided to thethreading carriage 128 with a pinch roll 1202 (see FIG. 12). In some ofthese examples, the pinch roll 1202 is rotated at a rotational speedthat matches a linear speed of movement of the metal substrate 102 as ituncoils from the coil 106.

In various examples, the threading carriage 128 includes the grippingwedge 602, and gripping the metal substrate 102 includes directing themetal substrate 102 through the gripping wedge 602 while the grippingwedge 602 is in the release position (see FIG. 9). After the metalsubstrate 102 is positioned relative to the gripping wedge 602, themethod includes closing the gripping wedge 602 to the gripping position(see FIG. 7) to grip the metal substrate 102. In some cases, thegripping wedge 602 grips the metal substrate 102 at a position that isoffset from the leading edge 132 of the metal substrate 102 (see FIG.9). In various aspects, gripping the metal substrate 102 with thegripping wedge 602 includes crimping the metal substrate 102 with thegripping wedge 602 to impart at least one lateral curvature across thewidth of the metal substrate 102.

According to other examples, the threading carriage 128 includes a pairof gripping rolls 1002. In these examples, gripping the metal substrate102 includes directing the metal substrate 102 between the grippingrolls 1002 and gripping the metal substrate 102 with the gripping rolls1002 at a position that is offset from the leading edge 132 of the metalsubstrate 102.

In certain examples, moving the threading carriage 128 towards the workstand 120 includes mechanically moving the threading carriage 128 alongthe track 134. In various cases, the threading carriage 128 is movedtowards the work stand 120 at a linear speed that matches a rotationalspeed of the coil 106.

In some examples, the method includes releasing the metal substrate 102from the threading carriage 128 when the leading edge 132 of the metalsubstrate 102 is at or proximate the work stand 120. According tovarious examples, the method optionally includes gripping the metalsubstrate 102 proximate to the trailing edge 133 of the metal substrate102 with the gripper 130, guiding the trailing edge 133 to the workstand 120, and disengaging the threading carriage 128 from the metalsubstrate 102 when the trailing edge 133 of the metal substrate 102 isproximate to the work stand 120.

In various cases, the method includes supporting a portion of the metalsubstrate 102 between the threading carriage 128 and the coil 106 withat least one rotating magnet 136 without contacting the metal substrate102. In some cases, the method also optionally includes controlling atension of the metal substrate 102 with the at least one rotating magnet136. In some cases, the method includes controlling a tension of themetal substrate 102 with at least two rotating magnets 136 by rotatingan upstream rotating magnet 136 in a first direction and rotating adownstream rotating magnet 136 rotates in a second direction that isopposite the first direction. In some aspects, the method optionallyincludes quenching the metal substrate 102 with at least one quench 138while guiding the metal substrate 102 to the work stand 120.

In some cases, the disclosed systems and methods allow for a metalsubstrate 102 to be threaded from a coil 106 into a work stand 120 withlow enough tension to avoid slippage in the coil 106 and to avoid orreduce surface markings on a surface of the metal substrate 102. In somecases, as mentioned above, the coil 106 is rotated at the same linearspeed as the movement of the metal substrate 102 to avoid generatingtension or slippage in the coil 106. The disclosed systems and methodsalso allow a coil at an elevated temperature to be rolled at elevatedtemperatures (e.g., greater than 500° C.) while reducing or eliminatingthe risk of damage to the surface of the metal substrate 102. In otherexamples, the metal substrate 102 and/or coil may not be at elevatedtemperatures. For example, the metal substrate may be at roomtemperature or various other temperatures less than 500° C.

It is noted that while the threading systems are described with respectto threading the leading edge of the metal substrate, they could also beused for guiding the trailing edge of the metal substrate during tailingout. For example, during tailing out, the threading systems could beused to control the tension in the metal substrate and the position ofthe metal substrate relative to the passline. In certain examples, usingthe threading systems during tailing out may produce less scratches orother defects on the metal substrate, may provide better temperaturecontrol (through magnetic heating or quenching), and may allow forhigher recovery of the metal substrate at the trailing edge. In certainexamples when the threading systems are used for tailing out, thethreading system may include a second gripper that moves along the sametrack 134 or other guide of the gripper 130. In other examples, the samegripper 130 may be used to guide the trailing edge during tailing out.In some of these examples, the gripper 130 may return to a positionproximate to the unwind mandrel 108 to engage the trailing edge of themetal substrate.

A collection of exemplary embodiments, including at least someexplicitly enumerated as “ECs” (Example Combinations), providingadditional description of a variety of embodiment types in accordancewith the concepts described herein are provided below. These examplesare not meant to be mutually exclusive, exhaustive, or restrictive; andthe invention is not limited to these example embodiments but ratherencompasses all possible modifications and variations within the scopeof the issued claims and their equivalents.

EC 1. A method of threading a metal substrate on a rolling millcomprising: receiving a coil of the metal substrate; uncoiling the metalsubstrate from the coil; and guiding the metal substrate to a work standof the rolling mill with a threading system.

EC 2. The method of any of the preceding or subsequent examplecombinations, wherein guiding the metal substrate to the work stand ofthe rolling mill comprises directing the metal substrate into a roll gapdefined between an upper work roll and a lower work roll of the workstand.

EC 3. The method of any of the preceding or subsequent examplecombinations, wherein guiding the metal substrate to the work standcomprises: guiding the metal substrate to a threading carriage of thethreading system; gripping the metal substrate with the threadingcarriage; and moving the threading carriage towards the work stand.

EC 4. The method of any of the preceding or subsequent examplecombinations, wherein the threading carriage comprises a pair ofgripping rolls, and wherein gripping the metal substrate with thethreading carriage comprises directing the metal substrate between thepair of gripping rolls and gripping the metal substrate with thegripping rolls at a position that is offset from a leading edge of themetal substrate.

EC 5. The method of any of the preceding or subsequent examplecombinations, wherein the position of the pair of gripping rolls isoffset from the leading edge such that when the leading edge is fed intoa roll gap of the work stand, the threading carriage is spaced apartfrom work rolls of the work stand.

EC 6. The method of any of the preceding or subsequent examplecombinations, wherein the threading carriage comprises a gripping wedge,and wherein gripping the metal substrate with the threading carriagecomprises directing the metal substrate through the gripping wedge andclosing the gripping wedge on the metal substrate at a position that isoffset from a leading edge of the metal substrate to grip the metalsubstrate.

EC 7. The method of any of the preceding or subsequent examplecombinations, further comprising adding stiffness to the metal substrateby closing the gripping wedge and crimping the metal substrate with thegripping wedge such that the metal substrate comprises at least onelateral curvature across a width of the metal substrate.

EC 8. The method of any of the preceding or subsequent examplecombinations, wherein adding stiffness to the metal substrate comprisescrimping the metal substrate with the gripping wedge such that the metalsubstrate comprises a plurality of lateral curvatures across the widthof the metal substrate.

EC 9. The method of any of the preceding or subsequent examplecombinations, wherein the threading carriage grips the metal substrateproximate to a leading edge of the metal substrate, and wherein themethod further comprises: disengaging the threading carriage from themetal substrate when the leading edge of the metal substrate isproximate the work stand; gripping the metal substrate proximate to atrailing edge of the metal substrate proximate an uncoiler; anddisengaging the threading carriage from the metal substrate when thetrailing edge of the metal substrate is proximate to the work stand.

EC 10. The method of any of the preceding or subsequent examplecombinations, further comprising quenching the metal substrate with atleast one quench sprayer while guiding the metal substrate to the workstand.

EC 11. The method of any of the preceding or subsequent examplecombinations, further comprising controlling a tension of the metalsubstrate with at least one rotating magnet while guiding the metalsubstrate to the work stand.

EC 12. The method of any of the preceding or subsequent examplecombinations, wherein the at least one rotating magnet is positionedbelow a passline of the metal substrate.

EC 13. The method of any of the preceding or subsequent examplecombinations, wherein the at least one rotating magnet comprises a pairof vertically aligned rotating magnets, and wherein guiding the metalsubstrate comprises guiding the metal substrate between the pair ofvertically aligned rotating magnets.

EC 14. The method of any of the preceding or subsequent examplecombinations, further comprising controlling tension, controlling ametal substrate temperature, guiding the metal substrate, modifying apassline of the metal substrate, or non-contact supporting the metalsubstrate with at least one rotating magnet.

EC 15. A system for threading a metal substrate on a rolling millcomprising: a threading carriage comprising a gripper configured to gripa metal substrate; and a track extending between an unwind mandrel and awork stand of the rolling mill, wherein the threading carriage ismovable along the track, and wherein the threading carriage isconfigured to guide and apply tension to the metal substrate between theunwind mandrel and the work stand.

EC 16. The system of any of the preceding or subsequent examplecombinations, wherein the gripper comprises a pair of gripping rollsconfigured to grip the metal substrate at a position that is offset froma leading edge of the metal substrate.

EC 17. The system of any of the preceding or subsequent examplecombinations, wherein the gripper comprises a gripping wedge configuredto close on the metal substrate at a position that is offset from aleading edge of the metal substrate.

EC 18. The system of any of the preceding or subsequent examplecombinations, wherein the gripping wedge is further configured to crimpthe metal substrate such that the metal substrate comprises at least onelateral curvature across a width of the metal substrate.

EC 19. The system of any of the preceding or subsequent examplecombinations, further comprising at least at least one rotating magnetbetween the unwind mandrel and the work stand.

EC 20. The system of any of the preceding or subsequent examplecombinations, wherein the at least one rotating magnet comprises a pairof vertically aligned rotating magnets, and the metal substrate isconfigured to pass between the pair of vertically aligned rotatingmagnets.

EC 21. A method of threading a metal substrate on a rolling millcomprising: receiving a coil of the metal substrate at an elevatedtemperature, wherein the elevated temperature is greater than 450° C.;uncoiling the metal substrate from the coil while the coil is at theelevated temperature; and guiding the metal substrate to a work stand ofthe rolling mill. In other examples, the coil of the metal substrate isreceived at room temperature or at a hot temperature less than 450° C.

EC 22. The method of any of the preceding or subsequent examplecombinations, wherein the elevated temperature is from 450° C. to 560°C.

EC 23. The method of any of the preceding or subsequent examplecombinations, wherein the metal substrate comprises aluminum, andwherein the elevated temperature is less than a melting point of themetal substrate.

EC 24. The method of any of the preceding or subsequent examplecombinations, wherein uncoiling the metal substrate comprisesunder-winding the metal substrate from the coil.

EC 25. The method of any of the preceding or subsequent examplecombinations, wherein uncoiling the metal substrate comprisesover-winding the metal substrate from the coil.

EC 26. The method of any of the preceding or subsequent examplecombinations, wherein the coil of the metal substrate comprises a foillayer between adjacent layers of the metal substrate within the coil,and wherein uncoiling the metal substrate from the coil comprisesseparating the foil layer from the metal substrate before guiding themetal substrate to the work stand.

EC 27. The method of any of the preceding or subsequent examplecombinations, wherein the foil layer comprises a metal having a highermelting point than a melting point of the metal substrate.

EC 28. The method of any of the preceding or subsequent examplecombinations, wherein the foil layer comprises steel.

EC 29. The method of any of the preceding or subsequent examplecombinations, wherein the foil layer has a hardness that is less than ahardness of the metal substrate.

EC 30. The method of any of the preceding or subsequent examplecombinations, wherein uncoiling the metal substrate comprisesover-winding the metal substrate. In other examples, uncoiling the metalsubstrate includes under-winding the metal substrate.

EC 31. The method of any of the preceding or subsequent examplecombinations, wherein uncoiling the metal substrate comprises breaking aweld between a leading edge of the metal substrate and the coil of themetal substrate.

EC 32. The method of any of the preceding or subsequent examplecombinations, wherein the work stand comprises an upper work roll and alower work roll, wherein the upper and lower work rolls define a rollgap, and wherein guiding the metal substrate to the work stand of therolling mill comprises directing the metal substrate into the roll gap.

EC 33. The method of any of the preceding or subsequent examplecombinations, wherein uncoiling the metal substrate comprises uncoilingthe metal substrate such that a passline of the metal substrate from anunroll point of the metal substrate is at a predetermined feed anglerelative to the roll gap.

EC 34. The method of any of the preceding or subsequent examplecombinations, wherein the passline of the metal substrate issubstantially parallel to a horizontal axis.

EC 35. The method of any of the preceding or subsequent examplecombinations, further comprising maintaining the predetermined feedangle of the passline by adjusting a vertical position of the coil.

EC 36. The method of any of the preceding or subsequent examplecombinations, wherein guiding the metal substrate to the work standcomprises: guiding the metal substrate to a threading carriage; grippingthe metal substrate with the threading carriage; and moving thethreading carriage towards the work stand.

EC 37. The method of any of the preceding or subsequent examplecombinations, wherein guiding the metal substrate to the threadingcarriage comprises directing the metal substrate with a pinch roll.

EC 38. The method of any of the preceding or subsequent examplecombinations, further comprising rotating the pinch roll to match alinear speed of movement of the metal substrate.

EC 39. The method of any of the preceding or subsequent examplecombinations, wherein the threading carriage comprises a pair ofgripping rolls, and wherein gripping the metal substrate with thethreading carriage comprises directing the metal substrate between thepair of gripping rolls and gripping the metal substrate with thegripping rolls at a position that is offset from a leading edge of themetal substrate.

EC 40. The method of any of the preceding or subsequent examplecombinations, wherein the position of the pair of gripping rolls isoffset from the leading edge such that when the leading edge is fed intoa roll gap of the work stand, the threading carriage is spaced apartfrom work rolls of the work stand. In certain examples,

EC 41. The method of any of the preceding or subsequent examplecombinations, wherein the threading carriage comprises a gripping wedge,and wherein gripping the metal substrate with the threading carriagecomprises directing the metal substrate through the gripping wedge andclosing the gripping wedge on the metal substrate at a position that isoffset from a leading edge of the metal substrate to grip the metalsubstrate.

EC 42. The method of any of the preceding or subsequent examplecombinations, further comprising adding stiffness to the metal substrateby closing the gripping wedge and crimping the metal substrate with thegripping wedge such that the metal substrate comprises at least onelateral curvature across a width of the metal substrate.

EC 43. The method of any of the preceding or subsequent examplecombinations, wherein the metal substrate comprises a plurality oflateral curvatures across the width of the metal substrate.

EC 44. The method of any of the preceding or subsequent examplecombinations, wherein moving the threading carriage towards the workstand comprises mechanically moving the threading carriage along atrack. In some examples, mechanically moving the threading carriageincludes using robotic arms

EC 45. The method of any of the preceding or subsequent examplecombinations, wherein moving the threading carriage comprises moving thethreading carriage at a linear speed that matches a rotational speed ofthe coil.

EC 46. The method of any of the preceding or subsequent examplecombinations, wherein the threading carriage grips the metal substrateproximate to a leading edge of the metal substrate, and wherein themethod further comprises: disengaging the threading carriage from themetal substrate when the leading edge of the metal substrate is at thework stand or past the work stand; gripping the metal substrateproximate to a trailing edge of the metal substrate close to theuncoiler; and disengaging the threading carriage from the metalsubstrate when the trailing edge of the metal substrate is proximate tothe work stand. In some examples, the threading carriage returns toproximate the uncoiler and engages the trailing edge of the metalsubstrate. In certain examples, a second threading carriage may be usedto engage the trailing edge. In various examples with gripping rolls,the roll pair may move the metal substrate close to the rolling mill,and the roll pair may then rotate without opening its gap to drive thestrip further, such as into the work stand of the rolling mill, andfinally releases the strip when the work stand grips the metalsubstrate.

EC 47. The method of any of the preceding or subsequent examplecombinations, further comprising quenching the metal substrate with atleast one quench sprayer while guiding the metal substrate to the workstand.

EC 48. The method of any of the preceding or subsequent examplecombinations, further comprising controlling a tension of the metalsubstrate with at least one rotating magnet while guiding the metalsubstrate to the work stand. In some examples, a plurality of rotatingmagnets are provided. In various examples, the rotating magnets areprovided to control tension, control strip temperature, guide the metalsubstrate, and/or control or modify the passline (e.g., reduce verticalsag or support of the strip).

EC 49. The method of any of the preceding or subsequent examplecombinations, wherein the at least one rotating magnet is positionedbelow a passline of the metal substrate.

EC 50. The method of any of the preceding or subsequent examplecombinations, wherein the at least one rotating magnet comprises a pairof vertically aligned rotating magnets, and wherein guiding the metalsubstrate comprises guiding the metal substrate between the pair ofvertically aligned rotating magnets. In other examples, only bottomrotating magnets may guide the strip.

EC 51. The method of any of the preceding or subsequent examplecombinations, wherein the pair of vertically aligned rotating magnetsrotate in opposite directions.

EC 52. The method of any of the preceding or subsequent examplecombinations, wherein the at least one rotating magnet comprises a firstrotating magnet and a second rotating magnet downstream from the firstrotating magnet, and wherein the first rotating magnet rotates in afirst direction and the second rotating magnet rotates in a seconddirection that is opposite the first direction.

EC 53. The method of any of the preceding or subsequent examplecombinations, further comprising supporting the metal substrate with atleast one rotating magnet while guiding the metal substrate to the workstand. In further examples, the method includes controlling tension,controlling strip temperature, guiding the strip, and/or modifying orcontrolling the passline of the metal substrate with the at least onerotating magnet.

EC 54. A system for threading a metal substrate on a rolling millcomprising: a threading carriage comprising a gripper configured to gripa metal substrate; and a track extending between an unwind mandrel and awork stand of the rolling mill, wherein the threading carriage ismovable along the track, and wherein the threading carriage isconfigured to guide and apply tension to the metal substrate between theunwind mandrel and the work stand.

EC 55. The system of any of the preceding or subsequent examplecombinations, wherein the gripper is configured to grip the metalsubstrate while the metal substrate is at an elevated temperature,wherein the elevated temperature is greater than 450° C.

EC 56. The system of any of the preceding or subsequent examplecombinations, wherein the elevated temperature is from 450° C. to 560°C.

EC 57. The system of any of the preceding or subsequent examplecombinations, wherein the elevated temperature is less than a meltingpoint of the metal substrate.

EC 58. The system of any of the preceding or subsequent examplecombinations, further comprising the unwind mandrel.

EC 59. The system of any of the preceding or subsequent examplecombinations, wherein the unwind mandrel is configured to support a coilof the metal substrate such that the metal substrate uncoils in anunder-wind direction.

EC 60. The system of any of the preceding or subsequent examplecombinations, wherein the unwind mandrel is configured to support a coilof the metal substrate such that the metal substrate uncoils in anover-wind direction.

EC 61. The system of any of the preceding or subsequent examplecombinations, wherein the unwind mandrel is vertically adjustable inorder to control the passline.

EC 62. The system of any of the preceding or subsequent examplecombinations, further comprising a pinch roll configured to direct themetal substrate from the unwind mandrel to the threading carriage and torotate at a rotational speed that matches a linear speed of movement ofthe metal substrate.

EC 63. The system of any of the preceding or subsequent examplecombinations, wherein the gripper comprises a pair of gripping rollsconfigured to grip the metal substrate at a position that is offset froma leading edge of the metal substrate. In some examples, the grippingrolls include one or more lateral curvatures (e.g., through bending,variable radii along the axis of the rolls, etc.).

EC 64. The system of any of the preceding or subsequent examplecombinations, wherein the gripper comprises a gripping wedge configuredto close on the metal substrate at a position that is offset from aleading edge of the metal substrate.

EC 65. The system of any of the preceding or subsequent examplecombinations, wherein the gripping wedge is further configured to crimpthe metal substrate such that the metal substrate comprises at least onelateral curvature across a width of the metal substrate in order tocontrol the stiffness of the leading edge.

EC 66. The system of any of the preceding or subsequent examplecombinations, wherein the gripping wedge is configured to crimp themetal substrate such that the metal substrate comprises a plurality oflateral curvatures across the width of the metal substrate in order tocontrol the stiffness of the leading edge.

EC 67. The system of any of the preceding or subsequent examplecombinations, further comprising a mechanical mover that is configuredto move the threading carriage along the track.

EC 68. The system of any of the preceding or subsequent examplecombinations, wherein the mechanical mover comprises at least one of awire, a rack and pinion, a chain, or a drive motor.

EC 69. The system of any of the preceding or subsequent examplecombinations, wherein the threading carriage further comprises a releaseconfigured to release the gripper from the metal substrate when themetal substrate is at the work stand.

EC 70. The system of any of the preceding or subsequent examplecombinations, further comprising at least one quenching station betweenthe unwind mandrel and the work stand.

EC 71. The system of any of the preceding or subsequent examplecombinations, further comprising at least at least one rotating magnetbetween the unwind mandrel and the work stand.

EC 72. The system of any of the preceding or subsequent examplecombinations, wherein the at least one rotating magnet is positionedbelow a passline of the metal substrate.

EC 73. The system of any of the preceding or subsequent examplecombinations, wherein the at least one rotating magnet comprises a pairof vertically aligned rotating magnets, and the metal substrate isconfigured to pass between the pair of vertically aligned rotatingmagnets.

EC 74. The system of any of the preceding or subsequent examplecombinations, wherein the pair of vertically aligned rotating magnetsare configured to rotate in opposite directions.

EC 75. The system of any of the preceding or subsequent examplecombinations, wherein the at least one rotating magnet comprises a firstrotating magnet and a second rotating magnet downstream from the firstrotating magnet, and wherein the first rotating magnet is configured torotate in a first direction and the second rotating magnet is configuredto rotate in a second direction that is opposite the first direction.

EC 76. The system of any of the preceding or subsequent examplecombinations, wherein the at least one rotating magnet is configured tosupport the metal substrate between the unwind mandrel and the workstand, control tension, control strip temperature, guide the metalsubstrate, and/or modify or control the passline of the metal substrate.

EC 77. The system of any of the preceding or subsequent examplecombinations, wherein the gripper comprises a pair of gripping rollsconfigured to grip the metal substrate.

EC 78. The method of any of the preceding or subsequent examplecombinations, further comprising adding stiffness to the metal substrateby adding a diameter profile along a length of a gripping roll such thatthe metal substrate comprises at least one lateral curvature across awidth of the metal substrate.

EC 79. The method of any of the preceding or subsequent examplecombinations, wherein the threading carriage grips the metal substrateproximate to a leading edge of the metal substrate, and wherein themethod further comprises: disengaging the threading carriage from themetal substrate when the leading edge of the metal substrate is grippedby a recoiler configured to rewind the metal substrate into a coil, suchas after the work stand.

The above-described aspects are merely possible examples ofimplementations, merely set forth for a clear understanding of theprinciples of the present disclosure. Many variations and modificationscan be made to the above-described example(s) without departingsubstantially from the spirit and principles of the present disclosure.All such modifications and variations are included herein within thescope of the present disclosure, and all possible claims to individualaspects or combinations of elements or steps are intended to besupported by the present disclosure. Moreover, although specific termsare employed herein, as well as in the claims that follow, they are usedonly in a generic and descriptive sense, and not for the purposes oflimiting the described invention, nor the claims that follow.

That which is claimed is:
 1. A method of threading a metal substrate ona rolling mill comprising: receiving a coil of the metal substrate;uncoiling the metal substrate from the coil; guiding the metal substrateto a work stand of the rolling mill with a threading system, whereinguiding the metal substrate to the work stand comprises: guiding themetal substrate to a threading carriage of the threading system;gripping the metal substrate with the threading carriage; and moving thethreading carriage towards the work stand, wherein the threadingcarriage comprises a gripping wedge, and wherein gripping the metalsubstrate with the threading carriage comprises directing the metalsubstrate through the gripping wedge and closing the gripping wedge onthe metal substrate at a position that is offset from a leading edge ofthe metal substrate to grip the metal substrate, and wherein the methodfurther comprises adding stiffness to the metal substrate by closing thegripping wedge and crimping the metal substrate with the gripping wedgesuch that the metal substrate comprises at least one lateral curvatureacross a width of the metal substrate.
 2. The method of claim 1, whereinadding stiffness to the metal substrate comprises crimping the metalsubstrate with the gripping wedge such that the metal substratecomprises a plurality of lateral curvatures across the width of themetal substrate.
 3. The method of claim 1, wherein the threadingcarriage grips the metal substrate proximate to a leading edge of themetal substrate, and wherein the method further comprises: disengagingthe threading carriage from the metal substrate when the leading edge ofthe metal substrate is proximate the work stand; gripping the metalsubstrate proximate to a trailing edge of the metal substrate proximatean uncoiler; and disengaging the threading carriage from the metalsubstrate when the trailing edge of the metal substrate is proximate tothe work stand.
 4. The method of claim 1, further comprising quenchingthe metal substrate with at least one quench sprayer while guiding themetal substrate to the work stand.
 5. The method of claim 1, furthercomprising controlling tension, controlling a metal substratetemperature, guiding the metal substrate, modifying a passline of themetal substrate, or non-contact supporting the metal substrate with atleast one rotating magnet.
 6. A system for threading a metal substrateon a rolling mill comprising: a threading carriage comprising a gripperconfigured to grip a metal substrate; and a track extending between anunwind mandrel and a work stand of the rolling mill, wherein thethreading carriage is movable along the track, and wherein the threadingcarriage is configured to guide and apply tension to the metal substratebetween the unwind mandrel and the work stand, wherein the grippercomprises a gripping wedge configured to close on the metal substrate ata position that is offset from a leading edge of the metal substrate,and wherein the gripping wedge is further configured to crimp the metalsubstrate such that the metal substrate comprises at least one lateralcurvature across a width of the metal substrate.
 7. The system of claim6, further comprising at least at least one rotating magnet between theunwind mandrel and the work stand.
 8. The system of claim 7, wherein theat least one rotating magnet comprises a pair of vertically alignedrotating magnets, and the metal substrate is configured to pass betweenthe pair of vertically aligned rotating magnets.